Great British railway journeys

Mount Snowdon is so high that trains on a normal railway line would be unable
to climb its slopes. So, since 1894, a Swiss-inspired "rack and pinion"
train has been used to ferry passengers up and down. "Between the
tracks is a rack of teeth, with which a pinion or cog wheel on the train
meshes, thus preventing the train from sliding down the track,"
explains Bunce. The Snowdon train is the only railway of its type in
Britain.